Method and apparatus providing automatic connection announcement from a modular network device to a network management point

ABSTRACT

A method of provisioning modular network devices is described. A generic configuration is placed on a device; the configuration comprises commands for configuring interfaces associated the device. At the device, each interface associated with the device is configured with at least one command associated with the configuration. The device then attempts to connect with a management point through the current interface. If the current interface can connect to the management point, then an inventory of all interfaces associated with the device is self-initiated and automatically communicated by the device to the management point. In other embodiments, based on the inventory information, a configuration template containing relative interface references may be resolved into a permanent device configuration that includes absolute interface references. As a result, modular network devices in which interfaces of various types are installed at different slot locations may acquire a permanent configuration automatically from a remote management station.

PRIORITY CLAIM; CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit as a Continuation of application Ser.No. 10/422,227, filed Apr. 23, 2003, entitled “Method And ApparatusProviding Automatic Connection Announcement From A Modular NetworkDevice To A Network Management Point,” by Arnold Stamler and IkramullahMohammed, the entire contents of which is hereby incorporated byreference for all purposes as if fully set forth herein, under 35 U.S.C.§120. The applicants hereby rescind any disclaimer of claim scope in theparent application or the prosecution history thereof and advise theUSPTO that the claims in this application may be broader than any claimin the parent application.

This application is related to U.S. application Ser. No. 10/422,231,Attorney Docket No. 50325-0774, filed on Apr. 23, 2003, entitled “MethodAnd Apparatus For Automatically Synchronizing A Unique Identifier Of ANetwork Device”, by Arnold Stamler, the entire contents of which ishereby incorporated by reference for all purposes as if fully set forthherein. The applicants hereby rescind any disclaimer of claim scope inthe related application or the prosecution history thereof and advisethe USPTO that the claims in this application may be broader than anyclaim in the related application.

FIELD OF THE INVENTION

The present invention generally relates to deploying network devices.The invention relates more specifically to a method and apparatusproviding automatic provisioning for modular network devices.

BACKGROUND OF THE INVENTION

The approaches described in this section could be pursued, but are notnecessarily approaches that have been previously conceived or pursued.Therefore, unless otherwise indicated herein, the approaches describedin this section are not prior art to the claims in this application andare not admitted to be prior art by inclusion in this section.

Broadband network access is now widely available. In general,subscribers to broadband service that is provided by a service provideruse a network device, such as a broadband router or gateway, to connecta personal computer or other end station to the service provider'snetwork and obtain service. Automatic network configuration provisioningsystems are now available for use in generating and downloading sets ofconfiguration instructions, or configuration files, for network devicesthat are deployed in the field to subscribers of services provided byservice providers. Such provisioning can occur automatically, withoutrequiring a subscriber to manually enter configuration commands, andwithout requiring a technician associated with a network serviceprovider to visit the subscriber and configure the device.

In one example approach, a vendor manufactures of customer premisesequipment (CPE) network devices, and “drop-ships” the CPEs to thepremises of subscribers of a network service provider. The CPEs areshipped with a generic bootstrap configuration that is copied from orgenerated at the vendor based on a standard template or format specifiedby the service provider. When a subscriber installs and powers-up a CPE,under control of the bootstrap configuration the CPE uses an interfacespecified in the bootstrap configuration to contact a configurationserver associated with the service provider. The configuration serverdownloads a permanent, application-specific configuration to the CPE,which executes the received configuration and begins normal operation.

Standardized, template-based configurations contain configurationcommands that refer to line cards, modules and interfaces by a specificslot or chassis location. Thus, the use of standardized templateconfigurations requires that all the target hardware devices have aknown, fixed hardware configuration, uniform for all networksubscribers, so that the configuration can contain proper fixedreferences to slot locations.

However, many network devices are now made using a modular architecturein which the location of line cards and other components may vary fromdevice to device, and may vary among units of the same device model. Asthe slots on a modular device are identical, any type of line card canbe plugged into any slot. Thus, the manufacturer can package one devicewith multiple line cards in many combinations. Typically network devicescomprise a chassis that supports one or more line cards for processingATM, serial, or Ethernet data. Each line card has one or moreinterfaces. Configuration commands determine specific functions of theinterfaces. For example, in a bootstrap configuration template, aparticular configuration command in the template may instruct the deviceto configure slot 1, interface 3 and configure it as a serial interface.A service provider may use the same template for 1,000 devices that aredeployed to its subscribers. However, if the devices are modular and donot have a line card in slot 1, or the device has a card in that slotthat cannot provide a serial interface, the template configuration willnot work and the device cannot obtain its permanent configuration.

While the inventory within a device chassis is deterministic at time ofshipping from manufacturing, line-cards or modules are manually placedin the chassis. Therefore, controlling which line-cards or modulesultimately are placed in which slots is a labor-intensive problem,subject to human error and has had no known cost-effective, scalablesolution. Therefore, to date, there has been no way to automate theconfiguration of modularized network devices with templates.

In this scenario, past approaches to automatic provisioning have not metwith success. For example, with modularized routers that use atemplate-based configuration that specifies a particular slot that doesnot actually contain a line card with a necessary interface, the routercannot connect to a configuration server or other management point. Now,however, with modularized devices and the increasing use of dropshipment to deliver devices directly to subscribers, service providersneed an improved automated provisioning process that can still useconfiguration templates.

In one known approach, Nortel Networks offers a customized templatemechanism residing in the network management domain that allows theadministrator to specify that a configuration associated with a givenline card will only occur if that line card is in its correct intendedslot. Otherwise, a controlled failure is generated during theprovisioning of the device and the administrator is notified. Thisapproach does not address automation of deployment workflow.

Further, the large majority of modules and line cards that plug intoNortel devices are “dumb” and have no way of self-announcing themselvesupon device power-up or insertion or removal of a device. Even the fewernumber of newer intelligent cards simply self-announce physicalattributes such as type of card and slot insertion point, but theseattributes are inadequate to support automated provisioning of networkdevices. There is a need for a way to provide a high-level inventoryevent on-behalf of all cards in the device, including the set ofdevice-wide absolute references to all physical interfaces that can beprovisioned on each card. Further, there is a need to receive, at amanagement point, an inventory of unpopulated or empty slots within thedevice chassis. Having numerous other inventory details reported abouteach card would be beneficial. Such higher-level inventory informationis essential to the automation of network management functions such asprovisioning.

In another known approach, Cisco Systems, Inc. offers a “Config Express”service that allows customers to specify a device configuration thatCisco writes into each router or other device at manufacturing time.This service is available for fixed chassis routers only, and it cannotbe extended to modular devices.

In another known approach, many cable modems of various vendors supporta mechanism for automatically acquiring their configuration. However,such devices are not modular devices, and they need a TFTP agent serverfor the mechanism to work. Most service providers will not use TFTPprotocols to communicate to subscriber CPE devices because of lack ofsecurity. Thus, there is a need for an approach that is compatible withsecure protocols.

Further, the approach of some vendors such as Netility is to licenseimbedded technology to support automated communication of configurationinformation to devices. However, this approach does not support modulardevices in which the location of line cards and modules may vary.

Based on the foregoing, there is a clear need for an approach forautomatically provisioning of modular network devices.

There is a specific need for an approach that can use pre-specifiedconfiguration templates to deliver a consistent configuration to modulardevices.

There is also a particular need for an automated configuration approachthat is compatible with drop shipment practices.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings and in whichlike reference numerals refer to similar elements and in which:

FIG. 1A is a block diagram depicting a network context in which anautomatic provisioning system may be used;

FIG. 1B is a flow diagram showing a high level overview of a process forautomatically provisioning a network device;

FIG. 2A is a flow diagram that illustrates a high level overview of oneembodiment of a method for identifying an interface that can connect toa configuration server;

FIG. 2B is a flow diagram that illustrates further steps in the methodof FIG. 2A;

FIG. 2C is a flow diagram showing a process for automaticallyprovisioning a device;

FIG. 2D is a flow diagram showing a process of device-initiatedinventory reporting;

FIG. 3 is a block diagram that illustrates an operational example; and

FIG. 4 is a block diagram that illustrates a computer system upon whichan embodiment may be implemented.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A method and apparatus for providing automatic provisioning for modularnetwork devices is described. In the following description, for thepurposes of explanation, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Itwill be apparent, however, to one skilled in the art that the presentinvention may be practiced without these specific details. In otherinstances, well-known structures and devices are shown in block diagramform in order to avoid unnecessarily obscuring the present invention.

Embodiments are described herein according to the following outline:

-   -   1.0 General Overview    -   2.0 Structural Overview-Order and Provisioning Context    -   3.0 Method of Automatically Provisioning Network Devices        -   3.1 Overview        -   3.2 Process of Determining a Communication Channel        -   3.3 Self-Initiating a Device Inventory Report        -   3.4 Generating an Application-Specific Configuration        -   3.5 Operational Example    -   4.0 Implementation Mechanisms-Hardware Overview    -   5.0 Extensions and Alternatives

1.0 General Overview

The needs identified in the foregoing Background, and other needs andobjects that will become apparent for the following description, areachieved in the present invention, which comprises, in one aspect, amethod for provisioning modular network devices. A generic startupconfiguration is placed on the device; the configuration comprisescommands for configuring interfaces on the device. At the device, eachinterface on the device is configured with commands associated with theinterface. The device then attempts to connect with a management pointthrough the current interface. If the current interface can connect tothe management point, then an inventory of all interfaces associatedwith the device is self-initiated and automatically communicated by thedevice to the management point.

In other aspects, based on the inventory information, a configurationtemplate containing relative interface references may be resolved into apermanent device configuration that includes absolute interfacereferences. As a result, modular network devices in which interfaces ofvarious types are installed at different slot locations may acquire thesame permanent configuration, automatically under supervision of aremote management station.

In other aspects, the invention encompasses a computer apparatus and acomputer-readable medium configured to carry out the foregoing steps.

In one aspect, the approaches herein provide, unlike past approaches,reliable transmission of timely accurate device modular inventoryinformation that is initiated from the device dynamically or“just-in-time” in response to changes to the device's hardwareconfiguration, whether such changes occur online or across power-cyclesof a device. Further, an automated configuration approach for modulardevices is provided using the device-initiated inventory functionality.The approaches herein may be used for devices that are delivered as partof deployment of enterprise networks, or as part of deploying customerpremises equipment to subscribers of network service providers, or inother contexts.

This approach generally comprises three components: establishing aconnection from the device to a management point for transmission ofdevice inventory information; initiation of inventory messages from thedevice to the management point, in which the messages describe theactual inventory of the device; and automatically generating aconfiguration for the device, based on the inventory messages, by themanagement point.

Establishment of a channel for sending modular inventory is generallyperformed as follows. A device dynamically discovers which of itsinterfaces, across multiple media types, can self-initiate a channel tothe management point for the sending of modular inventory. Beforephysically deploying devices, a set of parameterized configurationcommands are entered into the device's bootstrap configuration. Theparameterized configuration commands facilitate performing, within thedevice, a dynamic self-discovery of interfaces through pinging themanagement point, across multiple interfaces and interface types. Theself-discovery process continues across all slots until connectivity tothe management point is detected.

Because the bootstrap configuration approach is generic with respect toall deployed devices of a given type, a service provider can define asingle bootstrap configuration that can be applied in an automatedfashion at pre-deployment time, even as part of the manufacturingprocess. The bootstrap configuration provides the minimal functionalitynecessary for a device to announce its inventory and then acquire itsactual application configuration.

Sending modular inventory from the device to the management point isperformed as follows. Once a connection is established from the deviceto the management point, the device sends an inventory of its modules,interface names and slot insertion points to the management point. SSLor other encryption approaches may be used to enforce security. The sameinventory information is published each time the device contacts themanagement point, and dynamically whenever any modules are inserted orremoved online.

Unlike prior approaches, the present approaches provide the only knownmechanism by which a device initiates reporting that there has been achange to internal inventory and also detects and reports, on behalf ofall plugged-in cards, key information values such as Module ID asextracted from the module's hardware PROM, slot number, and a set ofabsolute references to all interfaces that can be provisioned on eachcard. The approaches herein are also unique in that they include aninventory of unpopulated or empty slots within the chassis. Further, theinventory message is initiated from the device in response to onlineinsertion or removal of cards, as well as changes in hardwareconfiguration across power-cycles. Self-initiation of an inventorymessage also solves the problem of that a device could be behind afirewall.

Consumption of modular inventory information by the management point forautomatically custom building configuration generally is performed asfollows, in one embodiment. At administration time, each device islogically represented in a database as a logical device object thatcorresponds to the device. Associated with this device object is a setof logical objects that correspond to the modules that are expected bythe provisioning system to be plugged into the device's chassis.Associated with each module object is a configuration template thatexpresses the intended configuration of interfaces that reside on themodule. Each template uses a syntax that avoids any slot references thatwould be inherent in interface references directed to a slot-pluggablemodule. Rather than have absolute interface references, the templateuses relative interface references, relative to the 1^(st) or zero^(th)interface of a given type.

A concatenation of all templates for all modules associated with thedevice object forms a kind of single parametric configuration, pendinginstantiation upon receipt of inventory from a specific instance ofdevice. Upon receiving inventory information from the device, themanagement point updates its database, and then resolves the objecttemplate relative interface references for each module into absoluteinterface references as reported in the inventory from the device.

In one specific embodiment, based on an inventory message from a device,the management point selects a database entry for the device object.Modules are identified by Module ID (Product code). For each module IDwithin the inventory from the device, the management point finds amatching module ID in the device object. For each interface type orprefix in the inventory message from the device, the management pointsorts interfaces by their numerical value, and substitutes inventoryfrom the sorted list into corresponding device object relativeinterfaces of the same type, from lowest to highest numerical value.

Based on the above process, the parametric configuration of the deviceobject which contains relative interface references is resolved into afully instantiated configuration which includes absolute slot specificinterface references. The final configuration is returned to the device.

In general, the approaches herein provide for generating a high-levelinventory event or report relating to all cards in a network device. Theinventory event includes each card's type, slot, and a set ofdevice-wide absolute references to all physical interfaces that can beprovisioned on each card. Further, the approaches herein include aninventory of unpopulated or empty slots within the device chassis.Additionally, numerous other inventory details are reported about eachcard. Such higher-level inventory information facilitates automation ofnetwork management functions such as provisioning. Furthermore, thedynamic, “just-in-time” reporting of device inventory, which isinitiated from the device in response to online insertion or removal ofcards, as well as changes in hardware configuration across power-cycles,represents a significant improvement over past approaches.

Using the approaches herein, service providers can achieve sharp costreductions. By eliminating a “truck roll” to the customer premises,savings of hundreds of dollars per CPE device is realized. Further, theaccelerated rate of deployment facilitated by this solution translatesinto a proportionally accelerated clearing of order backlogs for devicevendors.

The approaches herein also may be used for device discovery to supportvendor sales of service contracts. Currently, the cost of a servicecontract to the customer typically depends on the type and amount ofhardware inventory that is present in the network. Further, devicesbehind a firewall cannot be polled using SNMP polling discoverymechanisms. As a result, a vendor may lose service contract revenuebecause the vendor cannot determine what network hardware is actually inuse at a particular customer that uses a firewall. Using the approachesherein, devices self initiate and announce inventory from the deviceoutbound to the management point. Thus, a device behind a firewall isnot an obstacle.

2.0 Structural Overview—Provisioning Context

FIG. 1A is a block diagram depicting a system for synchronizing theunique identifier of a device, according to one embodiment.

A system 100 comprises a Vendor 110 of a Device 130, a Service Provider120 of the Device 130, and a Subscriber 140 to the Device 130. Althoughvendors, service providers, and subscribers may order many devices, forthe purposes of illustrating a clear example, System 100 depicts onesuch device (130). Vendor 110, Service Provider 120, and Subscriber 140may communicate with one another electronically or through manual means.As one example, Vendor 110 is communicatively coupled to ServiceProvider 120 and to Subscriber 140 through a network 105, which maycomprise one or more local area networks, wide area networks,internetworks, etc. At various times or points in the processesdescribed herein, Device 130 is located within domains of Vendor 110,Service Provider 120, or Subscriber 140, as indicated by dashed lines106 a, 106 b, 106 c.

Device 130 comprises a Hardware Identifier 131 that is assigned toDevice 130 by a Manufacturing Division 112 associated with Vendor 110.The Manufacturing Division 112 may assign any sequence of characters asthe Hardware Identifier 131. For example, these characters may include,but are not limited to, alphanumeric and special characters such as “@”,“#”, “$”, “%”, “*”.

According to one embodiment, a serial number associated with somecomponent of Device 130, such as its chassis or CPU, is used as theHardware Identifier 131. The Device 130 may acquire its HardwareIdentifier 131 using any of several mechanisms, includingself-discovery. Examples of identifier values that Device 130 may“self-discover” and assign to Hardware Identifier 131, include, but arenot limited to, the chassis serial number or the MAC address. Accordingto another embodiment, the Hardware Identifier 131 may be manuallyinputted into Device 130 as part of manufacturing or an initialconfiguration process.

Device 130 further comprises a Unique Identifier 134 that uniquelyidentifies Device 130. For example, the value “xyz” may be assigned asthe Unique Identifier 134 for Device 130 whereas the value “abc” may beassigned as the unique identifier for a different device. In contrast toHardware Identifier 131, Unique Identifier 134 is changeable when Device130 is in operation. Configuration commands may instruct Device 130 toadopt its Hardware Identifier 131 as its Unique Identifier 134, or toadopt some other value as its Unique Identifier.

At the time of manufacturing, Device 130 is configured with an InstalledConfiguration 132. The Installed Configuration 132 may include commandsfor changing the value of the Unique Identifier 134. Device 130 includesan Operating System 133, among other things, for executing commandsassociated with the Installed Configuration 132.

According to one embodiment, Operating System 133 includes an InventoryReporting Agent 133A comprising instructions which, when executed byDevice 130, cause the device to self-initiate a report of its internalinventory of line cards and interfaces to Management Point Systems 126or other elements of Service Provider 120. Specific mechanisms forinitiating an inventory report and the format of a report are describedfurther below.

Vendor 110 may comprise a Purchasing Division 111 to handle orders fromService Provider 120 for Device 130 and a Manufacturing Division 112 formanufacturing the Device 130. According to one embodiment, PurchasingDivision 111 comprises an Order Entry application 111A for communicatingpurchasing information from Vendor 110 to Service Provider 120.According to one embodiment, the Order Entry application 111A is used tocommunicate the Hardware Identifier 131 for Device 130 to ServiceProvider 120. For example, Order Entry application 111A may communicatethe Hardware Identifier 131 for Device 130 to Service Provider 120 inresponse to a request from the Service Provider for current status aboutan order for the device.

Configuration System 112A is a mechanism, provided by the ManufacturingDivision 112, for the Service Provider 120 to communicate theconfiguration that the Service Provider 120 wants the Vendor 110 to useas the Installed Configuration 132 for a particular order or Device 130.According to one embodiment, Configuration System 112A is ConfigurationExpress as provided by Cisco Systems, Inc., San Jose, Calif. ServiceProvider 120 communicates a Generic Configuration 112B to the Vendor 110through Configuration System 112A. According to one embodiment, theGeneric Configuration 112B is a bootstrap configuration that is loadedas the Installed Configuration 132 of Device 130 when manufacturing ofDevice 130 is complete.

According to one embodiment, the Generic Configuration 112B comprises abootstrap configuration. The Generic Configuration 112B containsinstructions which, when executed by Device 130, enable the Device todetermine which of several line cards or interfaces in the Device cancommunicate through network 105 to Configuration Server 122. Specificprocesses for self-discovering a connected interface are describedfurther below.

In one embodiment, Service Provider 120 comprises an EngineeringDivision 121, a Device Object 123, a Purchasing Agent 125, aConfiguration Template 124, a Configuration Server 122, and ManagementPoint Systems 126. Engineering Division 121 defines the GenericConfiguration 112B and communicates the Generic Configuration 112B tothe Vendor 110 with the Configuration System 112A.

Device Object 123 is a logical representation of the Device 130 that ismaintained by Service Provider 120 for purposes of tracking deviceorders and deployments. According to one embodiment, the Device Object123 maps an Administration Unique ID 123A to a Hardware Identifier 123B.The Administration Unique ID 123A holds a value that is internallygenerated by Service Provider 120 to uniquely identify a device that hasbeen ordered by Subscriber 140 before the Service Provider receives ahardware identifier or other unique identifier that is actuallyassociated with a particular device such as Device 130. TheAdministration Unique ID 123A uniquely identifies a device that aparticular subscriber, such as Subscriber 140, has ordered or will orderin the future. Later, an order for a device may become associated with aparticular device, such as Device 130, by assigning Hardware Identifier131 of Device 130 to the Hardware Identifier 123B of Device Object 123.For example, the Order Entry application 111A communicates the HardwareIdentifier 131 of Device 130 to the Service Provider 120 in response toa request from the Service Provider for an update about a particularorder. Service Provider 120 may then assign the value of the HardwareIdentifier 131 to the Hardware Identifier 123B in the Device Object 123.

According to one embodiment, Purchasing Agent 125 places an order withthe Vendor 112 for a device to be used by Subscriber 140. The PurchasingAgent 125 may receive the value associated with the AdministrationUnique Identifier 123A from Device Object 123 to place and track theorder. The Purchasing Agent 125 may communicate the value of theAdministration Unique Identifier 123A to the Configuration System 112Aas part of placing an order with Vendor 110.

According to one embodiment, the Configuration Template 124 is apartially complete configuration that the Service Provider 120specifically wants installed as the Installed Configuration 132 forDevice 130 for Subscriber 140. For example, the Configuration Template124 may contain commands or parameter values that are specific to anoperating environment or business environment of Subscriber 140.Further, the Configuration Template 124 contains one or moresubstitution strings for which values derived from an actual inventoryof Device 130 are substituted before the configuration is provided tothe device.

Thus, while the Generic Configuration 112B may be sufficient for initialconfiguration of all devices deployed by the Service Provider 120, for aparticular Subscriber 140, a final or application-specific configurationis needed. In an embodiment, the final or application-specificconfiguration is created based on populating the Configuration Template124 with values derived from an inventory report received from thedevice. Specific mechanisms for substituting values and generating afinal configuration based on a template are described further below.

According to one embodiment, Configuration Template 124 contains one ormore Substitution Strings 124A, which acts as a placeholder or markerthat specifies a location for substituting in a value that is obtainedfrom an inventory report received from Device 130. Using mechanismsdescribed further below, the Configuration Template 124 is processed bysubstituting inventory values to create a final configuration, which isdownloaded to Device 130 and becomes the Installed Configuration 132.Substitution Strings 124A may be used for substituting any desiredparameter value into a configuration template.

According to one embodiment, the Configuration Server 122 creates andtransmits a final configuration based on the Configuration Template 124to Device 130 at Subscriber 140. According to one embodiment,Configuration Server 122 creates the final configuration based onConfiguration Template 124 when Device 130 connects to the ConfigurationServer and requests a configuration. According to one embodiment, theConfiguration Server 112 is the Cisco CNS 2100 Series IntelligenceEngine, from Cisco Systems, Inc.

According to one embodiment, Management Point Systems 126 are systemsthat are interested in Device 130, its inventory, or information that itgenerates. Examples of Management Point Systems 126 include, but are notlimited to, billing systems, provisioning systems, and fault detectionsystems. As depicted, Management Point Systems 126 are part of ServiceProvider 120, however, Management Point Systems 126 may be any systemsthat are informed when inventory in Device 130 changes or when otherevents of interest occur with respect to the Device.

FIG. 1B is a flow diagram showing a high level overview of a process forautomatically provisioning a network device.

In block 160, the process automatically determines a communicationchannel that can reach a management station. Details of example methodsfor determining the communication channel are described below. Ingeneral, a device self-discovers an interface that has connectivity to amanagement station, regardless of the physical chassis location of aline card or module that contains the interface.

In block 162, the communication channel is used to contact aconfiguration server. The configuration server may form a part of themanagement station that was contacted in block 160. In block 164, theidentity of the communication channel, and other device inventoryinformation, is automatically reported on the communication channel tothe management station. Unlike past approaches, a report of theinventory information is self-initiated by the device.

In block 166, an application-specific device configuration is generated.The configuration references correct interface locations of the device.

In block 168, the application-specific device configuration is received,typically by download to the device that performed steps 160 to 164,inclusive. Block 166 is shown in phantom lines in FIG. 1B because it maybe performed by the management station. In contrast, other steps of FIG.1B generally are performed by a network device, such as a subscriber CPEdevice.

3.0 Method of Automatically Provisioning Modular Network Devices 3.1Overview

According to one embodiment, automatically provisioning modular networkdevices is facilitated by a configuration command that can instruct thedevice to connect to a configuration server without specifying whichinterface to use for the connection.

In one specific embodiment, the configuration command is “cnsconnect-intf” and forms part of the command-line interface (CLI) of anetwork device operating system. The command resembles, in syntax, the“interface” command that forms part of the Internetworking OperatingSystem (IOS) from Cisco Systems, Inc., except that no interface numberor slot is specified, only an interface prefix. The command instructsthe device to connect to a configuration server termed “cns” using anyavailable interface matching the specified prefix.

Upon executing the specified configuration command, a device willsucceed in connecting to a configuration server regardless of thechassis location of particular modules. In one embodiment, this commandis stored in a startup configuration of the device. When the devicereboots, the command causes the device to iterate through all interfacesin the device that have the same prefix type.

For each interface, a well-formed “interface” CLI command is internallybuilt and applied dynamically using the iterated interface chassis slotand interface number. The internally created “interface” command makesuse of any sub-mode command lines that were specified in the original“cns config connect-intf” command. Each such internally created“interface” command is then applied internally to the device.

Thereafter, the device sends an inquiry to the configuration server,such as a “ping,” and waits for a response. If no response is receivedwithin a specified timeout period, then the next interface is processedin the same manner. This process proceeds until the configuration serveris contacted successfully.

Immediately subsequent to connection, the device presents to theconfiguration server its device unique identifier, and a specificationof the line card inventory, module inventory, and chassis slot numberinsertion point for each module in the device. In one embodiment, theinventory is provided in an inventory message in that conforms to XMLformat. The inventory message reports, by device product-number, theslot chassis location of each module.

Based on the unique identifier of the connecting device and the variousproduct numbers reported in the inventory message, the configurationserver locates a matching configuration template in a device informationrepository. For example, in one embodiment, the configuration serversearches a directory or other repository for pre-defined CLI templatesfor the main chassis configuration and a sub-configuration for eachmodule.

The configuration server then processes the configuration templates intoapplication-specific templates for the device. In an embodiment, theconfiguration server substitutes the actual slot numbers from theinventory message into slot number parameters of the templates. Thus,non-specific slot identifiers in the templates are resolved intoslot-specific, subscriber-specific configuration commands that match thetrue module and slot hardware configuration of the target device. Theconfiguration server returns the application-specific configuration tothe target device. The target device invokes a command parser andapplies the final configuration.

In one embodiment, device functions of the foregoing process may beimplemented using a dedicated agent that runs under control of thenetwork device operating system. In one specific embodiment, a CNS agentof Cisco IOS is modified to implement the functions described herein,and the configuration server is the Cisco IE2100.

In one implementation, in the IE2100 configuration server, the followingmodifications were made. Added to the device object, which representsthe chassis global configuration of a device, is the sub-device objectthat represents a hardware module plugged into the chassis. Associatedwith the sub-device is a template for which a new syntax was invented torefer to device interfaces in a manner that is relative to the modulethe interfaces are physically defined on. For example, an interface isreferenced as the 1^(st) interface, 2^(nd) interface, etc. This relativeinterface syntax removes the problem of having to pre-specify fixed slotnumbers that cannot be predicted in a template. At run time, an actualslot number and interface number are substituted for the relativeinterface references using values obtained from the IOS XML inventorymessage that was received for the owner sub-device or device objects.

A pre-configured bootstrap configuration includes the “cns configconnect-intf” command in the startup configuration. The bootstrapconfiguration is specified by a service provider as part of an onlineorder for one or more devices. In one specific embodiment, the serviceprovider uses “Config Express,” an existing web-based service that isintegrated with the Cisco Connection Online order entry system. UsingConfig Express, the service provider specifies a general subscribernon-specific bootstrap configuration intended to provide connectivity tothe configuration server. The manufacturer then applies thisconfiguration to all the devices of that order in a totally automatedmanufacturing step.

When the foregoing process is integrated with an automated order entryand configuration system, the process provides an extended end-to-endelectronic business solution that inter-relates and provides for initialsubscriber order-entry; Cisco manufacturing; Cisco shipping; finaldevice provisioning; and subscriber billing.

3.2 Process of Determining a Communication Channel

A process of automatically determining, through internal self-discovery,at least one communication channel to a management station, and storinga configuration that retains knowledge of the discovery.

In the approach herein, a new form of configuration command is providedthat has different syntax than prior commands and also causes differentbehavior in a configured device. In past approaches, a configurationcommand in a template configuration has instructed a device to connectto a management point using a particular interface of a particular type.For example, the command “interface ATM 1/0” has been used, followed bya set of sub-commands. This syntax has instructed a device to configurethe 0^(th) interface of the line card at slot 1 of the device as an ATMinterface, to apply the sub-commands to that interface, and then attemptto connect to the management point with that interface.

In contrast, in the present approach, a command of the form

-   -   Cns config connect-intf<interface-type>        is provided. For example, a bootstrap configuration may have the        command “connect interface ATM,” followed by sub-commands that        apply to ATM interfaces. In response to executing the “connect        interface” command, a device internally self-discovers all        corresponding interfaces of all line cards and modules. For        example, if the basic command is “connect interface ATM,” then        the device self-discovers all ATM interfaces available in all        line cards and modules. For each particular interface, the        device determines the correct syntax for referencing that        interface. Further, the device internally builds a well-formed        command for the particular interface, and attempts to configure        the particular interface by applying the sub-commands to it.

The device then attempts to connect to the management point by issuing a“ping” command, or the equivalent, and receiving an acknowledgment fromthe management point. An acknowledgment failure may occur, for example,if no network cable is connected to the particular interface, or becausea cable is connected to an interface of the same type in a differentslot location. If connectivity is not achieved to the management point,the device rolls back or “undoes” the configuration of the particularinterface, and attempts the same process on the next discoveredinterface. The foregoing process is repeated iteratively across allinterfaces until connectivity is achieved.

If no connectivity is achieved for all interfaces of a particular type,then the next interface type is checked in the same way. For example,all ATM interfaces are checked first, and then all frame relay or serialinterfaces are investigated. Such checks are defined in multiplecontiguous blocks of configuration commands, in which one block appliesto each interface technology type.

FIG. 2A is a flow diagram that illustrates a high level overview of oneembodiment of a method for identifying an interface that can connect toa configuration server. FIG. 2B is a flow diagram that illustratesfurther steps in the method of FIG. 2A.

Referring first to FIG. 2A, in block 202, a connection configuration isreceived. For example, a device receives a bootstrap configuration aspart of the manufacturing process. The bootstrap configuration may havethe format shown in Table 1, which is described in detail below.

Blocks 204 to 216 represent a process of iterating through interfaces ofa device to identify an interface that has connectivity to a managementstation. In block 204, an index variable I is set to reference the firstinterface of the first module of the device. In block 206, the Ithinterface is configured by applying sub-configuration commands to it. Inblock 208, the device attempts to issue a ping command, or theequivalent, using the Ith interface, to reach the management station.

In block 210, a test is performed to determine whether the ping attemptis successful. If the ping is successful, then connectivity isestablished, and the device may proceed to request a permanentconfiguration, as discussed below in connection with FIG. 2C, FIG. 2D.If the ping is not successful, then in block 212, the configurationapplied at block 206 is removed.

In block 214, a test is performed to determine if the Ith interface isthe last interface in the module then under consideration. If so, thencontrol continues at FIG. 2B. Otherwise, if other interfaces in the samemodule remain to be tested for connectivity, then in block 216 the valueof I is incremented and control returns to block 206 to consider thenext available interface.

Referring now to FIG. 2B, block 218 is reached when all interfaces of aparticular module have been tested; in block 218, a test is performed todetermine whether the then-current module is the last module in thedevice of a particular type. In this context, “type” refers totechnology type, such as ATM, serial, etc. If additional modules arepresent in the device, then in block 220, the next module of the samemodule type is considered and I is updated to reference the firstinterface in that module. Control then continues at block 206 of FIG.2A.

However, if the test of block 218 determines that the last module of thecurrent type has been considered, then in block 222 a test is performedto determine whether the device contains other modules of other types.If so, then in block 224 the next module type is considered. Otherwise,control reaches block 226 when all interfaces of all modules of allmodule types have been tested. If no connectivity is then available,then an error message is generated.

Table 1 depicts an example bootstrap configuration, according to oneembodiment.

Line No. Commands  1 !  2 Version 12.2  3 !  4 ip domain lookup  5 ipname-server 171.69.2.133  6 ip name-server 171.70.168.183  7 ipname-server 171.68.226.120  8 ip domain name cisco.com  9 ! 10 usernamet3uplink password 0 cisco 11 ! 12 ip host-routing 13 ! 14 interfacevirtual-Template 1 15 ip address negotiated 16 ppp authentication papchap 17 ! 18 cns config connect-intf Serial number 3 ping-interval 30retries 10 19 config-cli no ip address 20 config-cli encapsulationframe-relay 21 config-cli keepalive 15 22 config-cli fair-queue 23config-cli shutdown 24 config-cli no shutdown 25 config-cli frame-relayinterface-dlci 100 ppp Virtual-Template1 26 config-cli cns idvirtual-Template1 ipaddress 27 config-cli cns id Virtual-Template1ipaddress event 28 config-cli ip 0.0.0.0 0.0.0.0 & 29 ! 30 ! 31 cnsconfig connect-intf POS number 3 ping-interval 30 retries 10 32config-cli ip address slarp retry 2 33 config-cli crc 32 34 config-clipos framing sdh 35 config-cli pos scramble-atm 36 config-cli pos flag c222 37 config-cli pos flag sls0 2 38 config-cli cns id & ipaddress 39config-cli cns id & ipaddress event 40 config-cli ip route 0.0.0.00.0.0.0 & 41 ! 42 ! 43 cns config connect-intf ATM number 3ping-interval 30 retries 10 44 config-cli no atm ilmi-keepalive 45config-cli pvc 14/14 46 config-cli inarp 1 47 config-cli ip addr inarp48 config-cli encapsulation aa15snap 49 config-cli cns id & ipaddress 50config-cli cns id & ipaddress event 51 config-cli ip route 0.0.0.00.0.0.0 & 52 ! 53 cns config connect-intf Async ping-interval 30 retries10 54 config-cli ip address negotiated 55 config-cli encapsulation ppp56 config-cli dialer in-band 57 config-cli dialer string 79537 58config-cli dialer-group 1 59 config-cli async default routing 60config-cli async mode interactive 61 config-cli cns id & ipaddress 62config-cli cns id & ipaddress event 63 config-cli ip route 0.0.0.00.0.0.0 & 64 line-cli modem InOut 65 line-cli transport input all 66line-cli autoselect ppp 67 line-cli stopbits 1 68 line-cli speed 11520069 line-cli flowcontrol hardware 70 ! 71 dialer-list 1 protocol ippermit 72 cns password cnsboot 73 cns inventory event 74 cns inventoryconfig 75 cns config initial 10.1.27.10 event no-persist 76 ! 77 end

Using the configuration of Table 1, a device can send information to amanagement point over any frame relay, POS or ATM interface located inany slot. If no such interface succeeds in contacting the managementpoint, then the device attempts to establish a dial-up connection overthe conventional telephone system using any available asynchronous modemin any slot. The configuration contains no specific interface or slotreferences. Connection to the management point is supported overmultiple media types.

Lines 18 to 28 of Table 1 instruct a device to attempt a connection to amanagement point using available serial interfaces. Line 18 instructsthe device to use a ping interval of 30 seconds and to attempt 10retries before declaring a timeout. For all serial interfaces in allslots, the configuration of lines 19 to 28 is executed within thecontext of each specific interface. The ampersand (“&”) in line 28signifies a substitution macro for the specific instance of interfacethat is referenced in a particular iteration. The configuration attemptsto ping the configuration server on each serial interface; if there isno response, then the process iterates to the next serial interface; ifall serial interfaces are tried without success, then the next interfacetype is attempted.

In the example of Table 1, POS is the next interface type, as indicatedby lines 31 to 40. The process described immediately above is repeatedfor all available POS interfaces. If the POS ping process isunsuccessful, then in lines 43 to 51, ATM interfaces are attempted. Forthe POS interfaces and ATM interfaces, a substitution macro is signifiedby the “&” symbol in lines 40 and 51, respectively.

If the device cannot establish ATM connectivity to the configurationserver, then an asynchronous modem connection is attempted, as shown bylines 53-69. If all asynchronous modem interfaces are attempted and noconnectivity is achieved to the management point, then no exchange ofinventory or configuration information can occur, and an error messagemay be generated.

In lines 72 to 75 of Table 1, configuration communicates inventoryinformation to the management point as part of requesting a permanent,application-specific configuration.

Although the foregoing process has been described in terms of iteratingthrough interfaces, the general principles described herein areapplicable to any logical entity that forms a part of a line card andcan be used for connectivity.

3.3 Self-Initiating a Device Inventory Report

In general, a process is provided by which a device self-initiates areport of its internal inventory. In one feature, the devicesuccessfully communicates the report to a configuration server. Inanother feature, the report comprises specified elements. In yet otherfeatures, the report is generated in response to a configuration change;the process may be interrupt-driven or device-driven.

FIG. 2D is a flow diagram showing a process of device-initiatedinventory reporting. In block 272, a device creates an inventory thatdescribes absolute interface references for all interfaces in thedevice. In block 274, the inventory is communicated to a managementpoint. Block 274 may involve communicating the inventory over thecommunication interface that was identified in the process of FIG. 2A,FIG. 2B. The inventory may be expressed as an XML message.

According to one embodiment, a device self-initiates an inventory reportby sending a request to the management point to provide a permanentconfiguration for the device. Included in the request is a value thatuniquely identifies the device. The device provides an inventory of eachmodule type that is plugged into its chassis. For each module type, aninventory of interfaces on each particular module is provided. Eachinterface is identified using syntax that may be used in a configurationcommand to correctly access the associated interface. In one specificembodiment, the inventory is provided in XML form.

Using the inventory information provided in the configuration requestmessage from the device, a management point can then generate anapplication-specific configuration or permanent configuration for thedevice, as described in the next section.

In one embodiment, the inventory is self-initiated by the device inresponse to a change in the configuration or inventory of the device.For example, when the device is powered up, or if modules are insertedinto or removed from the chassis, the device initiates an inventorymessage to the management point. The inventory message updates theentire inventory of the device and thereby informs the management pointabout any changes that occurred. In an alternative embodiment,successive inventory messages provide only information about changes ininventory since the last inventory message sent by a device.

Further, in an embodiment, each inventory message identifies any slotsin a device that are empty, and contain no line cards or modules.

The approaches herein offer numerous improvements over past approaches.For example, in past approaches, Simple Network Management Protocol(SNMP) is used to announce changes in device hardware by sending an SNMPtrap. Management points have had to use several different techniques,which vary based on the device hardware that is involved, to determinewhat has changed in a device configuration based on a trap message. Forexample, management points have had to poll the device to obtain deviceinternal inventory information, and compare received responses to knowndetails about the inventory. This is complicated and often yieldserrors.

Further, the foregoing past approach cannot obtain information fromdevices that are secured behind firewalls, because by default mostfirewalls will not pass SNMP traffic. However, in the current approachthis problem is overcome because the device initiates messages outwardthrough the firewall.

3.4 Generating an Application-Specific Configuration

In general, a process is provided for resolving a set of relativeinterface references into absolute interface references based onreal-time inventory from the device. In the process, a genericmanagement point template configuration contains special characterssignifying substitution strings. When inventory information is receivedfrom the device, the generic template configuration is modified bysubstituting device-specific inventory values for the substitutionstrings. In contrast, in past approaches, templates referred to slotsand interface positions using fixed values.

FIG. 2C is a flow diagram showing a process for automaticallyprovisioning a device. In general, FIG. 2C represents processing stepsthat are performed by a management station. In block 242, an inventoryis received that describes absolute interface references for a device.For example, the inventory described herein with respect to FIG. 2D maybe received from a device at a management station.

In block 244, a template that describes relative interface referencesfor the device is located. Block 244 may involve retrieving, from arepository such as a directory or database, a template for a permanentdevice configuration based on a device type value that is received inthe inventory from the device.

In block 246, relative interface references in the configurationtemplate are resolved into absolute interface references based on thevalues that are received in the inventory from the device. In block 248,the resolved permanent configuration is downloaded to the device.

As an example, Table 2 depicts a management point template that may beused in relative interface resolution, according to one embodiment.

TABLE 2 EXAMPLE MANAGEMENT POINT TEMPLATE Line No. Commands 1 ! 2Interface Serial %Serial0% 3 ip address${LPDAP://this::attrName=IOSipaddress} 255.255.255.0 4 no shutdown 5 ! 6Interface Serial %Serial1% 7 ip address${LPDAP://this::attrName=IOSipaddress} 255.255.255.0 8 no shutdown 9 !

Table 2 depicts commands on line 2 and line 6 that include relativeinterface reference for serial interfaces. The relative interfaceaddresses may be replaced with absolute interface references from aninventory. For example, on line 2, the relative interface reference “%Serial0%” may be replaced with the absolute interface reference“Serial0/0” if this is appropriate based on information received fromthe device. Similarly, on line 6, the relative interface reference “%Serial1%” may be replaced with the absolute interface reference“Serial0/1”. In general, an example of syntax for a substitution stringis:

-   -   % <Type of interface><logical port number>%

According to an embodiment, the use of such relative references andtemplates with substitution strings also facilitates creating a computermemory representation of a device, as part of a management pointapplication, using more sophisticated data structures. In pastapproaches, a management point application would represent a device inapplication memory as a single logical object in a database, keyed to aunique device identifier, such as a chassis number. The device objectwould be created at the management point at the time that the managementpoint or its associated service provider issued an order for aparticular device.

In the present approach, at the time that a service provider orders adevice for delivery to a subscriber, a management point applicationcreates a main device object. The main device object represents and isbased on a chassis type of the device, and contains one or more subobjects. Further, the main device object is associated with or points toa configuration template, containing substitution strings of the typeshown above in Table 2. The management point maintains one configurationtemplate for each general type of device. For example, all main deviceobjects for all Cisco 2600 routers that are deployed by a particularservice operator are associated with the same configuration template.

Each sub object represents a module in the device. Based on theinventory, the management point dynamically creates or instantiates oneor more sub objects based on the modules that are discovered ininventory. Thus, there is one sub object for each line card. Each subobject maps to a module of the device, and each sub object may carry aname that corresponds to a module type. Each module generally comprisesa product identifier that is associated with a sub object. Sets ofconfiguration commands associated with an interface of a module may beassociated in the management point application with a corresponding subobject.

Such an object model also may be maintained in a persistent repositorythat is accessible to the management point. For example, an LDAPdirectory or database may be used.

Using this approach, a device may send a request for a permanentconfiguration to the management point. In the request, the deviceprovides its unique device identifier. At the management point, based onthe device identifier, the corresponding device object is located. Themanagement point then retrieves the configuration template that isreferenced by the device object. Values from the inventory message aresubstituted into the configuration template at locations indicated bythe substitution strings. As a result, a final device configuration iscreated. The final device configuration is then downloaded to the deviceand is executed by the device.

3.5 Operational Example

FIG. 3 is a block diagram illustrating an operational example of use ofan embodiment.

At numeral 1), a subscriber orders a device that comprises a pluralityof modules. At numeral 2), a device object is created for the device,and sub-objects are created for each of the modules. In this context,objects are programmatic entities that are created using softwareprocesses of the service provider for purposes of managing an order ofan end user.

At numeral 3), a generic or preliminary bootstrap configuration iscreated for the device. The bootstrap configuration comprises commandsfor different types of modules that may be present in the device, suchas an ATM module, serial module, Ethernet module, etc. At numeral 4),the bootstrap configuration is installed in the device. At numeral 5),the device is shipped to a subscriber.

At numeral 6), the subscriber manually inserts the modules into thedevice, if required. In other embodiments, the device is shipped withmodules installed. At numeral 7), the subscriber powers-up or boots thedevice.

At numeral 8), the bootstrap configuration discovers an interface thatmay be used for connecting to a management point. In one embodiment, thebootstrap configuration executes instructions that search through themodules and the interfaces on the modules to find one interface that maybe used for connecting to the management point. As the device iteratesthrough the interfaces, a command is built to configure a particularinterface and then the device attempts to ping the management point fromthe configured interface. If it cannot ping the management point, theconfiguration does not use that particular interface. An inventory ofthe interfaces is built as the device goes through the foregoingself-discovery process. At numeral 9), when the device is able to pingthe management point through an interface, the inventory along with adevice identifier is sent to the management point.

At numeral 10), the management point uses the device identifier tolocate a device object that corresponds to the device. At numeral 11),the management point examines the device object and identifies atemplate that includes commands with relative addresses for modules andinterfaces for the type of device that has contacted the managementpoint.

At numeral 12), the inventory, device object, sub-objects, and templateare used to create a permanent or application-specific configuration forthe device. To create the permanent configuration, the relativeinterface addresses in the template are resolved to absolute addressesfor the actual interfaces reflected in the inventory. At numeral 13),the configuration is transmitted to the device, where the configurationis installed.

At numeral 14), the device optionally may initiate furtherself-reporting of its inventory to the management point. According toone embodiment, this is done when the device configuration changes or anoperational change occurs in the device. For example, self-reporting ofinventory may occur when the device is powered down, powered up, or whena module is inserted or removed.

4.0 Implementation Mechanisms—Hardware Overview

FIG. 4 is a block diagram that illustrates a computer system 400 uponwhich an embodiment of the invention may be implemented. The preferredembodiment is implemented using one or more computer programs running ona network element such as a router device. Thus, in this embodiment, thecomputer system 400 is a router.

Computer system 400 includes a bus 402 or other communication mechanismfor communicating information, and a processor 404 coupled with bus 402for processing information. Computer system 400 also includes a mainmemory 406, such as a random access memory (RAM), flash memory, or otherdynamic storage device, coupled to bus 402 for storing information andinstructions to be executed by processor 404. Main memory 406 also maybe used for storing temporary variables or other intermediateinformation during execution of instructions to be executed by processor404. Computer system 400 further includes a read only memory (ROM) 408or other static storage device coupled to bus 402 for storing staticinformation and instructions for processor 404. A storage device 410,such as a magnetic disk, flash memory or optical disk, is provided andcoupled to bus 402 for storing information and instructions.

A communication interface 418 may be coupled to bus 402 forcommunicating information and command selections to processor 404.Interface 418 is a conventional serial interface such as an RS-232 orRS-422 interface. An external terminal 412 or other computer systemconnects to the computer system 400 and provides commands to it usingthe interface 414. Firmware or software running in the computer system400 provides a terminal interface or character-based command interfaceso that external commands can be given to the computer system.

A switching system 416 is coupled to bus 402 and has an input interface414 and an output interface 419 to one or more external networkelements. The external network elements may include a local network 422coupled to one or more hosts 424, or a global network such as Internet428 having one or more servers 430. The switching system 416 switchesinformation traffic arriving on input interface 414 to output interface419 according to predetermined protocols and conventions that are wellknown. For example, switching system 416, in cooperation with processor404, can determine a destination of a packet of data arriving on inputinterface 414 and send it to the correct destination using outputinterface 419. The destinations may include host 424, server 430, otherend stations, or other routing and switching devices in local network422 or Internet 428.

The invention is related to the use of computer system 400 for providingautomatic provisioning for modular network devices. According to oneembodiment of the invention, providing automatic provisioning formodular network devices are provided by computer system 400 in responseto processor 404 executing one or more sequences of one or moreinstructions contained in main memory 406. Such instructions may be readinto main memory 406 from another computer-readable medium, such asstorage device 410. Execution of the sequences of instructions containedin main memory 406 causes processor 404 to perform the process stepsdescribed herein. One or more processors in a multi-processingarrangement may also be employed to execute the sequences ofinstructions contained in main memory 406. In alternative embodiments,hard-wired circuitry may be used in place of or in combination withsoftware instructions to implement the invention. Thus, embodiments ofthe invention are not limited to any specific combination of hardwarecircuitry and software.

The term “computer-readable medium” as used herein refers to any mediumthat participates in providing instructions to processor 404 forexecution. Such a medium may take many forms, including but not limitedto, non-volatile media, volatile media, and transmission media.Non-volatile media includes, for example, optical or magnetic disks,such as storage device 410. Volatile media includes dynamic memory, suchas main memory 406. Transmission media includes coaxial cables, copperwire and fiber optics, including the wires that comprise bus 402.Transmission media can also take the form of acoustic or light waves,such as those generated during radio wave and infrared datacommunications.

Common forms of computer-readable media include, for example, a floppydisk, a flexible disk, hard disk, magnetic tape, or any other magneticmedium, a CD-ROM, any other optical medium, punch cards, paper tape, anyother physical medium with patterns of holes, a RAM, a PROM, and EPROM,a FLASH-EPROM, any other memory chip or cartridge, a carrier wave asdescribed hereinafter, or any other medium from which a computer canread.

Various forms of computer readable media may be involved in carrying oneor more sequences of one or more instructions to processor 404 forexecution. For example, the instructions may initially be carried on amagnetic disk of a remote computer. The remote computer can load theinstructions into its dynamic memory and send the instructions over atelephone line using a modem. A modem local to computer system 400 canreceive the data on the telephone line and use an infrared transmitterto convert the data to an infrared signal. An infrared detector coupledto bus 402 can receive the data carried in the infrared signal and placethe data on bus 402. Bus 402 carries the data to main memory 406, fromwhich processor 404 retrieves and executes the instructions. Theinstructions received by main memory 406 may optionally be stored onstorage device 410 either before or after execution by processor 404.

Communication interface 418 also provides a two-way data communicationcoupling to a network link 420 that is connected to a local network 422.For example, communication interface 418 may be an integrated servicesdigital network (ISDN) card or a modem to provide a data communicationconnection to a corresponding type of telephone line. As anotherexample, communication interface 418 may be a local area network (LAN)card to provide a data communication connection to a compatible LAN.Wireless links may also be implemented. In any such implementation,communication interface 418 sends and receives electrical,electromagnetic or optical signals that carry digital data streamsrepresenting various types of information.

Network link 420 typically provides data communication through one ormore networks to other data devices. For example, network link 420 mayprovide a connection through local network 422 to a host computer 424 orto data equipment operated by an Internet Service Provider (ISP) 426.ISP 426 in turn provides data communication services through theworldwide packet data communication network now commonly referred to asthe “Internet” 428. Local network 422 and Internet 428 both useelectrical, electromagnetic or optical signals that carry digital datastreams. The signals through the various networks and the signals onnetwork link 420 and through communication interface 418, which carrythe digital data to and from computer system 400, are exemplary forms ofcarrier waves transporting the information.

Computer system 400 can send messages and receive data, includingprogram code, through the network(s), network link 420 and communicationinterface 418. In the Internet example, a server 430 might transmit arequested code for an application program through Internet 428, ISP 426,local network 422 and communication interface 418. In accordance withthe invention, one such downloaded application provides for providingautomatic provisioning for modular network devices as described herein.

The received code may be executed by processor 404 as it is received,and/or stored in storage device 410, or other non-volatile storage forlater execution. In this manner, computer system 400 may obtainapplication code in the form of a carrier wave.

5.0 Extensions and Alternatives

Accordingly, a method and apparatus providing automatic provisioning ofmodular network devices have been described. The embodiments disclosedherein solve at least two problems associated with the management ofmodular devices: automated configuration deployment and reliablemaintenance of network inventory.

In one embodiment, the problem of automated configuration deployment issolved. In particular, modular equipment typically is deployed usingmanual pre-staging of the hardware by third party system integrationpartners. When economic conditions have been good, most serviceproviders have not considered a manual pre-staging approach to be aproblem. When economic conditions are unfavorable, the costs associatedwith manual pre-staging are considered significant. The automationcharacteristic of the approaches herein represents a major cost savingsfor deployment, by eliminating truck rolls and reducing the requirementsfor skilled network management personnel.

Further, the approaches herein solve the problem of how the networkmanagement inventory system can reliably gather network inventory thatis accurate and timely. Current inventory gathering methods consist of ahodgepodge of improvisations, including word-of-mouth, manuallypopulated desktop-based spreadsheets, and some limited use of SNMP. TheSNMP approach is only available when devices are not behind a firewallor NAT. These approaches also are available on modular devices onlyprovided the soft and hard configurations match up, so that there is atleast connectivity to the management point. The existence ofdiscrepancies between an inventory system database and the actualnetwork inventory is a known problem, especially in large networks.

In the foregoing specification, the invention has been described withreference to specific embodiments thereof. It will, however, be evidentthat various modifications and changes may be made thereto withoutdeparting from the broader spirit and scope of the invention. Thespecification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense.

1. An apparatus for provisioning modular network devices, the apparatuscomprising: one or more processors; a communication interface configuredto receive an inventory that describes absolute interface references forinterfaces associated with a device; a configuration server configuredto locate a template that describes relative interface references forthe interfaces associated with the device and to create a configurationfor the device by resolving the relative interface references with theabsolute interface references; wherein the communication interfacecommunicates the configuration to the device.
 2. An apparatus as recitedin claim 1, wherein: the communication interface is configured toreceive a unique hardware identifier of the device; and theconfiguration server is configured to locate the template by using theunique hardware identifier of the device.
 3. An apparatus as recited inclaim 2, wherein the unique hardware identifier of the device is achassis serial number for the chassis of the device.
 4. An apparatus asrecited in claim 1, wherein: the communication interface is configuredto receive a unique hardware identifier of the device; and theconfiguration server is configured to use the unique hardware identifierto locate a main device object associated with the device.
 5. Anapparatus as recited in claim 1, wherein: the communication interface isconfigured to receive unique module identifiers for modules associatedwith the device; the configuration server is configured to use theunique module identifiers to locate device sub objects for the modulesassociated with the device.
 6. An apparatus as recited in claim 1,wherein the configuration server is configured to customize commandsassociated with the configuration using information associated withdevice objects for the device.
 7. An apparatus as recited in claim 1,wherein the device comprises pluggable modules and the interfaces areinterfaces associated with the pluggable modules.
 8. An apparatus asrecited in claim 1, wherein the template comprises one or more interfaceidentifiers that specify (a) an interface type and (b) an interface namein the form of a substitution string.
 9. An apparatus as recited inclaim 1, wherein the template comprises one or more interfacesubstitution strings of the form % <Type of interface><logical portnumber>%, wherein “%” comprises any delimiter character, <Type ofinterface> specifies an interface type, and <logical port number>specifies a logical port number.
 10. An apparatus for provisioningmodular network devices, the apparatus comprising: one or moreprocessors; means for receiving an inventory that describes absoluteinterface references for interfaces associated with a device; means forlocating a template that describes relative interface references for theinterfaces associated with the device; means for creating aconfiguration for the device by resolving the relative interfacereferences with the absolute interface references; means forcommunicating the configuration to the device.
 11. An apparatus asrecited in claim 10, further comprising: means for receiving a uniquehardware identifier of the device; wherein the means for locatingfurther comprises means for using the unique hardware identifier of thedevice to locate the template.
 12. An apparatus as recited in claim 11,wherein the unique hardware identifier of the device is a chassis serialnumber for the chassis of the device.
 13. An apparatus as recited inclaim 10, further comprising: means for receiving a unique hardwareidentifier of the device; means for using the unique hardware identifierto locate a main device object associated with the device.
 14. Anapparatus as recited in claim 10, further comprising: means forreceiving unique module identifiers for modules associated with thedevice; means for using the unique module identifiers to locate devicesub objects for the modules associated with the device.
 15. An apparatusas recited in claim 10, wherein the means for creating the configurationfurther comprises means for customizing commands associated with theconfiguration with information associated with device objects for thedevice.
 16. An apparatus as recited in claim 10, wherein the devicecomprises pluggable modules and the interfaces are interfaces associatedwith the pluggable modules.
 17. An apparatus as recited in claim 10,wherein the template comprises one or more interface identifiers thatspecify (a) an interface type and (b) an interface name in the form of asubstitution string.
 18. An apparatus as recited in claim 10, whereinthe template comprises one or more interface substitution strings of theform % <Type of interface><logical port number>%, wherein “%” comprisesany delimiter character, <Type of interface> specifies an interfacetype, and <logical port number> specifies a logical port number.
 19. Acomputer-implemented method of provisioning modular network devices,comprising: receiving an inventory that describes absolute interfacereferences for interfaces associated with a device; locating a templatethat describes relative interface references for the interfacesassociated with the device; creating a configuration for the device byresolving the relative interface references with the absolute interfacereferences; communicating the configuration to the device; wherein themethod is performed by one or more computing devices.
 20. A method asrecited in claim 19, further comprising the steps of: receiving a uniquehardware identifier of the device; wherein the step of locating furthercomprises the step of using the unique hardware identifier of the deviceto locate the template.
 21. A method as recited in claim 19, wherein thedevice comprises pluggable modules and the interfaces are interfacesassociated with the pluggable modules.
 22. A method as recited in claim19, wherein the template comprises one or more interface identifiersthat specify (a) an interface type and (b) an interface name in the formof a substitution string.
 23. A computer-readable storage medium storingone or more sequences of instructions which, when executed by one ormore processors, cause performance of the method recited in claim 19.24. A computer-readable storage medium storing one or more sequences ofinstructions for automatically provisioning a modular network device,the computer-readable storage medium further storing a template having(1) one or more interface identifiers that specify (a) an interface typeand (b) an interface name in the form of a substitution string, whereineach substitution string is resolvable into an absolute interface nameby a management point based on device inventory information that isreceived at the management point from the device, and (2) one or moredevice interface configuration commands associated with each of theinterface identifiers.
 25. A computer-readable storage medium as recitedin claim 24, wherein each of the interface identifiers comprises one ormore interface substitution strings of the form % <Type ofinterface><logical port number>%, wherein “%” comprises any delimitercharacter, <Type of interface> specifies an interface type, and <logicalport number> specifies a logical port number.